To use stem cells, we should know how stem cell storage is being performed

Nowadays, stem cells are being used in many biological inventions and treatments of multiple diseases. But, before using these stem cells, we need to know stem cell storage. So that we can store it for long duration and use it when we need.

Stem cells are un-specialized or undifferentiated cells with the ability to replicate the functionality of any specific cell type inside the body. This characteristic of stem cells, referred to as totipotency, which enables them to perform healing functions in the body like repairing tissues, blood vessels and organs.

Stem cells are preserved in cryogenic tanks to preserve their viability. Stem cell storage options are constantly rising, as stem cell therapy is being rapidly recognized all over the world as a mainstream treatment for many health disorders.

Sources of Stem Cells- From Where, We Will Get These Cells for Stem Cell Storage

The primary sources of stem cells in the body, which have found applications in the field of stem cell therapy are: –

Umbilical Cord blood: It refers to blood remaining in the umbilical cord of a baby. It contains high concentrations of hematopoietic stem cells, which re-divide and multiply in quick time. It has been successfully used for stem cell therapy since 1989.

Placenta derived blood: It is the blood remaining in placenta after a baby’s delivery. It is a rich source of mesenchymal stem cells (MSC’s) which are found in the middle layer or mesoderm of bone marrow.

Bone marrow: Bone marrow is a fine source of mature stem cells. Stem cells are invasively extracted from the mesoderm (middle layer) of marrow of patient or donor with the help of a flexible tube.

Peripheral blood: Blood circulating through the body also consists of stem cells, though the quantity is limited.

Fat: Fat or adipose tissue is a rich source of mature stem cells, which may differentiate into other cell types such as bone, muscle, cartilage or neurons.

The richest sources of stem cells are umbilical cord blood and placenta derived blood. These contain high concentration of immature stem cells, which have greater chances of being accepted by host’s body immunity, in both autogenic and allogenic transplant operations.

Autogenic Stem Cells

Autologous stem cell transplant refers to the procedure in which stem cells are derived from the patient’s body. At first, these cells are collected from blood and stem cell storage is done in cryogenic conditions, using liquid Nitrogen.

This process is followed by exposure of patient to chemotherapy or irradiation, which enables the destruction of damaged cells. Then, the stem cells are reinserted intravenously into blood vessels i.e. via a tube placed in vein.

Allogenic Stem Cells

In allogenic stem transplant, a donor is selected such that their Human Leukocyte Antigens (HLA’s) are similar to those in the bone marrow of the recipient.

A human body consists of proteins on their white blood cells called HLA’s which like any other antigen trigger the production of antibodies to protect the body against foreign invading matters. These antigens are found in the mesenchymal stem cells of the marrow. The donor is generally a family member like parent or offspring.

In other cases, unrelated donors with matching antigens may be selected for stem cell transplantation. If antigens do not match, a metabolic disorder called Graft versus host disease (GVHD) is observed, which in turn gives rise to undesirable health reactions or metabolic complications in the body of recipient at cellular to organic level.

Steps Taken Before Stem Cell Storage

Stem cells need to be carefully preserved, until their requirement for transplantation is issued by a patient. This is because in the storage period, stem cells are susceptible to attack by saprophytic bacteria which act as to decompose the matter.

The area which facilitates stem cell storage and preservation of stem cells in ideal and aseptic conditions, for a pre-decided time period is referred to as a stem cell bank. If not stored in proper conditions, stem cells gradually lose their viability and therapeutic ability.

The quality assessment of stem cell storage units is done by international certifying agencies like Food and Drug Administration Act (FDA). Private or family stem cell banks store stem cell samples for autogenic transplant, while public stem banks store them for allogenic transplant.

Stem Cell Storage

Stem cells are frozen to about -150⁰C by immersing them in vapor phase Nitrogen in storage vessels. This process is called cryogenic preservation.

The term cryogenics refers to preservation by reducing ambient temperatures to below freezing point of water, so as to inhibit any microbial activity and maintain sterile conditions for increased shelf life of stored product.

Crystallization of water in the stem cell solution leads to cellular damage by mechanical disruption. Hence, the basic principle of stem cell preservation is the prevention of ice crystal formation.

For this, cooling rate needs to be optimal. If stem cells are cooled too quickly, intracellular crystal formation will take place. On the other hand, very slow cooling results in ice crystal formation within extra-cellular matrix.

Temperature reduction from ambient to subzero value say – 190⁰C, takes place in three stages:

In the first stage, the temperature of stored stem cells is brought to below -8⁰C, with the help of crystallization.

In the next stage, the solution is cooled to -40⁰C.

Finally, a temperature of 190⁰C is reached. The vessels where temperature is reduced to the cryogenic range are known as cryotanks. Aseptic conditions are maintained for the entire storage period.

Quality Improvement of Stem Cells

The quality of stored cells is assessed with the help of the following parameters

Total cell count (TNC): It refers to the measure of cell count after cord blood processing. The measurement of TNC is automated nowadays, with the help of a device known as flow cytometer.

Mononuclear cell count: It refers to the number of peripheral blood cells with a round nucleus. Examples of mononuclear cells are lymphocytes, monocytes, erythrocytes and granulocytes.

Types of Stem Cells

CD34+ cells: These refer to certain glyco-proteinaceous cells which promote inter-cellular adhesion. The population of CD34+ cells in the isolated stem cells is a determinant of rate of cell engraftment.

Colony forming units- granulocyte macrophage(CFU-GM): It generally refers to the subjective determination of the viability of stem cells and their multiplicative ability. In order to measure CFU, a minute portion of stem cell solutions is observed under the microscope, to examine cell division and subsequent colony formation.

Types of Cryopreservatives in Stem Cell Storage

A compound used as a protective layer during cryopreservation is known as cryoprotectant or cryo-preservative. Some of the cryopreservatives are:

Dimethyl sulphoxide(DMSO): It has the ability to diffuse quite rapidly through cell membrane. The most favorable concentration of DMSO is 10%.

Hydroxyethyl starch(HES): It is a polymer which instead of penetrating the cell, form a viscous shell over cell surface, preventing any flow of water as that might result in cellular dehydration.

Plasma Proteins eg. Albumin, lymphocytes

Sugars eg. Manitol, sorbitol

Place of Stem Cells Storage

After preservation, stem cells are stored in either aqueous or vapor phase of Nitrogen in a storage vessel at temperatures of -190⁰C. Prior to freezing, each cryoprotected cord blood unit is stored in a sealed over-wrap bag, so that every unit is insulated and quarantined separately within freezer.

Every liquid Nitrogen container used as a cryotank is equipped with a computerized control system which replenishes it with required amount of Nitrogen, whenever required.

An automated alarm system is provided as well. Liquid Nitrogen volume in every vessel is periodically monitored by safety personnel. For every year of stem cell storage, family banks will charge fee from the donor’s family.

Stem Cell Storage Problems

Limited scientific data regarding shelf life of stored stem cells: According to available information, cord blood can be stored for a maximum of 25 years. No such scientific data is available, which can help to determine if the shelf life of cord blood may be increased.

Toxicity of cryoprotectant: A protective compound is used during the freezing process which is known as cryo-protectant. Sometimes, this compound is known to have toxic effects. Current researches are focusing on finding an alternative material which could be used as protective layering that is harmless and non-toxic.

Expensive insurance with uncertainty of application: Private cord blood banks charge a high initial processing fee along with annual storage costs ranging between $90 and $175. Hence, one needs to spend a lot for biological insurance. However, the probability that the stored cell sample will actually be used for transplant is very low.

Metabolic disorders in recipient’s body: During stem cell storage, many anomalies might develop and cause side effects later in the recipient, after transplant operations, which are as follows:

Anaphylaxis: It is an indication of hypersensitivity to an external agent known as antigen. The body’s immune system responds through a severe allergic reaction Eg. Inflammation or redness in the affected area.

Histamine induced vasodialation, causing hypotension: Histamine is a nitrogenous compound which plays a significant role in stimulating immunity responses and regulatory mechanisms in the body. It is produced in white blood cells. It causes enlargement of blood vessels and hence fall in blood pressure(hypotension)

Dyspnea: It is also referred to as shortness of breath and is characterized by tightening of chest.

Nausea

Cramps in abdomen

Cardiovascular disorders like surges in blood pressure

Headache

Reversible encephalopathy: It is a severe condition arising due to reduced oxygen flow to brain.

Diseases cured by Stem Cells

Stem cell therapy refers to stem cell transplantation coupled with radiation or chemotherapy. It is an advanced medical technique used for curing diseases like

Autoimmune diseases like diabetes 1(juvenile diabetes)

Orthopaedic diseases like arthritis

Neurological diseases like Alzheimer’s disease

blood pressure related problems

Cord blood banking is used for treatment of tumors, which may be of the following categories.

Malignant

Non malignant

Acute Myeloid Leukemia

Aplastic Anemia

Neuroblastoma

Fanconi Anemia(genetic disorder)

Stem cell therapy effectively heals ailments like Fibromyalgia, Joint pain and Crohn’s disease. It has been associated with the treatment of congenital immunodeficiency, Krabbe disease and Diamond Blackfan syndrome. In future, stem cell therapy will find increased applications in fields like dental growth stimulation and dermatology.

Stem Cell Storage Cost – In India and Overseas

Stem Cell Storage Costs in India: Stem cell banking is gradually developing in India. Some of the premier family stem cell banks are Lifecell and Cordlife. The enrollment fee is to be paid at the time of registration. Stem cell storage fee is payable from the date of registration to a period of 20-25 years.

Name of bank

Storage fee( in Rs.)

Lifecell

3500(yearly)

Cordlife

60,000(25 years)

Stem Cell Storage Cost Overseas

United States:

U.S. has the largest market share in stem cell banking sector, owing to the availability of advanced equipments and latest technologies. Stem cell storage is that part of banking, which accounts for maximum expenditures.

Some of the leading stem cell banks in the world are situated in United States. Eg. Cryocell, Viacord. The donor family is required to pay an annual stem cell storage charge of $150 to $175 to any family stem cell bank in U.S.

United Kingdom:

At Bioeden, U.K., storage charges for umbilical cord blood is equivalent to £90 per year.

PreciousCells, U.K. is a family stem cell bank where samples of fat, bone marrow, cord blood as well as tooth are collected, tested, preserved and stored for transplantation.

Duration/term

Storage cost

a.

Fat/ bone marrow

10 years

£2,000

b.

Tooth

30 years

£1,400

c.

Cord blood

Annual

£50

China:

Shanghai Cord blood bank, a venture of Shanghai stem cell technology co-operative limited in China has a scheme where annual payment of RMB600 per unit of cord blood is to be paid by the donor. The cord blood bank also provides prepaid storage plans.

Storage term

Discount %

10-15 years

5

16-20 years

10

Canada:

In all private stem banks, the storage fee is $115 on yearly basis. Create Cord blood bank, Canada provides annual storage plan of $115 and a prepaid storage plan valid for 10 years, at a discounted value of $1,000 only.

Japan:

Established 1999, Stem Cell Institute Inc. is the largest family cord blood bank in Japan. It is ISO: 9001 certified. The donor family is required to pay total initial cost with prepaid ten year storage plan charges equivalent to 220,500 JPY.

Payment options on installment basis are also available. Service fee is refunded in case the stored stem cell sample is found to be inappropriate for transplantation.

Russia:

Hemobank, National oncology center of Russian Academy of sciences is a private cord blood bank situated in Moscow. The umbilical cord donor has to pay a contractual fee of 3000 rubles every year for cord blood storage, which is equivalent to 107 dollars.

I hope you find our stem cell storage article, valuable for you. And it will help you to get good knowledge of stem cell storage. For more articles related to health issues, stay tuned with us.